Conventionally, a puncture device for indwelling an outer needle (catheter) in a blood vessel is known as disclosed in Patent Documents 1 and 2, for example.
Such a puncture device is provided with an outer needle, an outer needle hub for retaining the outer needle, an inner needle whose tip portion is inserted in the outer needle, and a cylindrical inner needle hub for retaining therein a base portion of the inner needle.
In particular, the puncture device disclosed in Patent Document 1 will be described with reference to FIG. 50.
As shown in FIG. 50(A), this puncture device 100 is provided with an outer needle 102a, an outer needle hub 102b, an inner needle 103 whose tip portion is inserted in the outer needle 102a, and a cylindrical inner needle hub 101 for retaining therein a base portion of the inner needle 103.
Further, the use of the puncture device 100 will be described. As shown in FIG. 50(A), in a situation where a slide cover 104 is accommodated in the inner needle hub 101 and a tip 103a of the inner needle 103 has projected from a tip of the outer needle 102a, a puncture (paracentesis) is carried out on a patient's body 110.
Then, after moving the outer needle 102a into the body (see FIG. 50(B)), in a situation where the outer needle 102a is indwelled in the body, when the inner needle hub 101 is pulled towards the user, the slide cover 104 is extended and the tip 103a of the inner needle comes out of the body (see FIG. 50(C)).
By further pulling the inner needle hub 101 in the same direction, the tip 103a of the inner needle 103 is retained in the slide cover 104, without contacting a hand.
Subsequently, in such a situation, the inner needle hub 101 is rotated in a circumferential direction (see FIG. 50(D)), the whole slide cover 104 rotates in the same direction, and the holder 105 at the tip side is released (removed).
As a result, only the outer needle 102a is indwelled inside the body, and the inner needle hub 101 in which the inner needle 103 is accommodated can be removed, and the inner needle 103 can be discarded as it is (see FIG. 50(E)).
Further, the puncture device disclosed in Patent Document 2 is arranged such that, although not shown, in a situation where the outer needle is indwelled inside the body, by pushing a push piece provided for the inner needle hub, the inner needle can be accommodated inside the inner needle hub without touching the inner needle.